UNH professor to study impacts of ADHD treatment

DURHAM — For most teenagers, it's easy to focus on activities they like — video games, sports or watching television. But why do they lose that focus for more important things, like homework?

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By Jennifer Feals

seacoastonline.com

By Jennifer Feals

Posted Jul. 26, 2010 at 2:00 AM

By Jennifer Feals

Posted Jul. 26, 2010 at 2:00 AM

» Social News

DURHAM — For most teenagers, it's easy to focus on activities they like — video games, sports or watching television. But why do they lose that focus for more important things, like homework?

Through a two-year, $399,000 grant from the national Institutes of Health, University of New Hampshire Assistant Professor of Psychology Jill McGaughy will look closely at why this occurs, diagnosing Attention Deficit Hyperactivity Disorder and how its treatments affect normal adolescent brains. Work is being done in conjunction with Dr. Barry Waterhouse at Drexel University College of Medicine in Philadelphia.

"We know that there are diagnoses of ADHD based on behavior and very often mediations introduced to help children, but it's still poorly understood how to make that diagnosis based on behavior and the impact of those medications on the adolescent brain," McGaughy said. "We're also looking at differences in attention and how treating those subjects with medication used to treat ADHD changes the brain as it develops."

Using a rodent model, McGaughy and her team will study how adolescents learn to focus their attention on one task and then shift attention to another. They also will investigate parts of the adolescent brain that control the ability to stop doing activities that no longer bring positive consequences. Rats can be trained to do tasks similar to humans, McGaughy said. So researchers will train the rat to complete one main task and then get the rat to shift its attention. They will then make comparisons from the rat's behavior to human behavior.

"The great thing is, we can go in and look at their brain in a way we're unable to do with the human brain," she said. "It's become clear that psychiatric disorders or intentional impairments are being diagnosed in childhood or adolescence, but we don't have a lot of data from humans at that period. Adolescence is two weeks long in a rat; you can process the data in a different way."

By studying development of two areas of the adolescent brain, and a teenager's range of attention, researchers hope to better understand how ADHD drugs affect the attention abilities of normal adolescents. McGaughy is working from evidence that shows the adolescent prefrontal cortex is not as developed as an adult's, making it difficult for teens to modify their behavior. The group will also examine the orbitofrontal cortex — the part of the brain that controls someone's ability to stop doing something that isn't bringing positive results. Data suggests this area of a teen's brain isn't fully mature.

McGaughy and her team believe that adolescents, because their brain is in a different stage of development, have too little of the neurotransmitter norepinephrine, which works alongside adrenaline to give the body sudden energy in times of stress. Norepinephrine increases in adulthood and also can be increased by ADHD medication.

"What we are trying to understand is, if you look at a normal adolescent and give them a drug used to treat ADHD, does it make them look like an adult, and second of all, if you chronically give a drug to a developing brain, how does it change its growth?" she said.

From the study, McGaughy hopes to gain insight into two things. "Number one, that we can come up with clear behaviors for normal attention of an adolescent versus impaired attention. We don't want children taking medication that they don't need, and we want to give the right medication to children who need it," she said. "And (second), what's the difference in administering a drug to a brain that's developing versus one that is developed?"